List of top Electricity and Magnetism Questions

An infinite sheet of uniform charge \( \rho_s = 10\, {C/m}^2 \) is placed on the \( z = 0 \) plane. The medium surrounding the sheet has a relative permittivity of 10 . The electric flux density, in C/m\(^2\), at a point \( P(0, 0, 5) \), is: Note: \( \hat{a}, \hat{b}, \hat{c} \) are unit vectors along the \( x, y, z \) directions, respectively.

Capacitance $C$ of a parallel-plate structure is calculated as $20~\text{pF}$ using $C=\dfrac{\varepsilon_0\varepsilon_r A}{d}$. The value is then measured using an ideal LCR meter (no cable-capacitance error). Which reading is likely to be correct?
The force per unit length between two infinitely long parallel conductors, with a gap of 2 cm between them, is 10 $\mu$N/m. When the gap is doubled, the force per unit length will be _____ $\mu$N/m (rounded off to one decimal place).
For a circuit shown below, when switch is closed, the current $I_2$(s) is (assume $i(0^+)=0)$
For the circuit shown in the figure, the inductance across X-Y is
A capacitor is constructed using two concentric spheres and air as the dielectric medium (permittivity of air = \(8.854 \times 10^{-12} \, \text{F/m}\)). The radii of the inner and outer spheres are \(a = 10 \, \text{cm}\) and \(b = 15 \, \text{cm}\), respectively. The capacitance (in picofarads) is _________ (round off to 2 decimal places).
A conducting semi-circular loop of radius \( R = 0.1 \, \text{m} \), with its diameter centered at the origin, rotates in the \( x \)-\( y \) plane about the origin with a constant angular velocity, \( \omega = 20 \, \text{rad/s} \), as shown. A magnetic field of magnitude \( B = 2 \, \text{T} \) and normal to the \( x \)-\( y \) plane exists in the region \( x \geq 0 \) as shown. If the loop has a resistance of \( 2 \, \Omega \), and negligible inductance, the peak-to-peak current (in milliamperes) in the loop is _________ (round off to one decimal place)